Wang Guangsheng, Wang Zhigang. Development of Vacuum Heat-treatmentand Its Key Technique[J]. Journal of Materials Engineering, 1997, 0(4): 3-7,9.
The latest developments in vacuum quenching,vacuum tempering,vacuum and/or chemical heat-treatment were introduced.The prospect of these technologies has been pointed out after a discussion on key technique.
Zhang Shanqing. Study of Vacuum Heat Treatment Process of Ti Alloy Blades[J]. Journal of Materials Engineering, 1997, 0(4): 10-13.
The deformation,hydrogen content,and surface contamination produced during heat treatment of precision closed die TZTA11 Ti alloy blades are some key problems impairing the product quality.Vacuum heat treatment processing of the Ti alloy blades was investigated, and the optimum processing parameters for the Ti blades production were established to resolve above mentioned problems.These include vacuity1.2×10-2～1×10-3Pa for lowering hydrogen, three steped heating of 600,700,800℃ for contralling deformation.
Yi Guang. Homogeneity of Temperature in Vacuum Heat Treatment Equipment[J]. Journal of Materials Engineering, 1997, 0(4): 14-17.
The temperature homogeneity effected by many elements has an important role in course of designs for a body of vacuum heat treatment furnace.These elements,which was discussed exhaustively,contains a loss-on-heating sources,physical characteristic of materials,designs for a workpiece holder etc.For the temperature homogeneity to ensure in the vacuum furnace,at last,some measures were provided in this paper.
Wan Zhengxing. Orthopaedics of the Turbine Casing by Vacuum Heat Treatment[J]. Journal of Materials Engineering, 1997, 0(4): 18-21,24.
The casing of turbine engine,which is made from cast titanium alloy ZT3 and ZT4,may be distorted because a residual stress was caused by the casting and mechanical processing.The vacuum heat treatment can be used for eliminating residual stress on the turbine casing and the operational program has been provided in the light of an experimental results.It is shown that annealing temperature being used in casting blank is 650℃ for alloy ZT3 and 700℃ for alloy ZT4,and that the annealing temperature being used in eliminating residual stress,which was caused by the mechanical processing,is 600℃ for these alloys.
Su Yixing. Technology for Eliminating the“White Layer”from Nitriding Steel38Cr Mo Al by Vacuum Heat-treatment[J]. Journal of Materials Engineering, 1997, 0(4): 22-24.
As a resault of changing of technologic parameter,the phasesε+ζ named “white layer”may appear in the microstructure of nitriding steel38Cr Mo Al.This microstructure possesses an unfavourable affection on parts which were made of that material.A molecular nitrogen,which was separated from the white layer,escapes from a surface of parts when heat-treated in vacuum.The results show that this technology has good engineering feasibility on the industies.
Wu Jianshe. Trouble Analysis of Vacuum System of the Vacuum Furnace[J]. Journal of Materials Engineering, 1997, 0(4): 25-27.
The vacuum of which vacuum heat treatment equipment is using can′t often achieved the standards during an operation.These troubles have been analyzed and have been e-liminated,which occurred to the vertical vacuum quench furnace in oil or in air.
Zhao Zhenfu. Experimentof Heat Treatmentin Type L12 13-Horizontal Vacuum Fur-nace[J]. Journal of Materials Engineering, 1997, 0(4): 28-29.
Structural feature and technical specification of type L1213-horizontal vacu-um furnace is presented. The experiment of vacuum heat treatment by means of different metal materials shown that the vaccum furnace is suitable to some aeronautical structural materials,and the furnace has wider applicability.
Liu Liansheng. Contamination of Precision Alloy from Vacuum Heat Treatment[J]. Journal of Materials Engineering, 1997, 0(4): 30-31.
The contamination which may appear in a vacuum heat treatment of precision alloy has been discussed and the contaminative origin and its danger such as oxidization of surface,carburizing,descarbonization,depletion of elements etc,has been analyzed concisely. At last,preventive measures were proposed.
Li Wenyu. Deformation and Its Control of Landing Gear Components of Aircraftafter Vacuum Heat Treatment[J]. Journal of Materials Engineering, 1997, 0(4): 32-34.
The deformation condition of large steel 300M components of aircraft landing gear after vacuum heat treatment was experimentally investigated.Some measures to control and to reduce the deformation,such as heating slowly,preheating at 600℃/1.5h,proper suspending, etc.are put forward.
Li Dongsheng, Tan Qingcheng, Song Mingdao, Yuan Xiaoming, Miao Xingqi. Development of Domestic Brake Assemblies of the Aircraft Boeing737,Boeing767and MD82[J]. Journal of Materials Engineering, 1997, 0(4): 36-39.
The research and manufacture of the brake assemblies for an advanced large passenger airplanes,such as Boeing737,Boeing767and MD-82,had been accomplished on the basis of the FAA technical standard TSO-C26c,the CAAC techinical standard CTSO-C26c and the airworthiness standard CCAR-25.Those CAAC standards are equivalent to these FAA stan-dards in specifications.The results show that properties of domestic brake assemblies achieved and/ or exceeded the level of similar imports according as the property testof material,the ground simulated test,the test flight and the use of airline has been completed.
Qi Lehua. Research on the Solidifying Characteristics of Zinc Alloy by Liquid Metal Forging Process[J]. Journal of Materials Engineering, 1997, 0(4): 40-42.
In this paper,the solidification process of Zn Al4Cu3 alloy during casting and liquid metal forging has been studied by means of experimental method.The influence of pressureon the temperature fields during the solidification process of liquid metal has been investigated.The variation of temperature at the different positions of the die and workpiece under the different pressure and punch′s temperature was measured and analysed.The solidifying characteristicsof liquid metal forging has been discussed.According to the experiments and calculation,it hasbeen shown that the solidifying velocity in the liquid metal forging process is increased about1 0times compared with that in the gravity casting.
Zhang Lefu, Xie Changsheng. Development of Material Scientific Databases[J]. Journal of Materials Engineering, 1997, 0(4): 43-46.
Material scientific database is the foundation of modern manufacturing technologies and concepts,as well as the effecient method for learning material knowledge and using proper material products to reduce cost in making high quality products.In this article,material scientific databases and the material information standard are introduced.
Wu Jiamei, Xie Jizhou. Manufacture of Crack Source and Determination of Residual Cycle Life for FGH95Powder Metallurgical Turbine Disk[J]. Journal of Materials Engineering, 1997, 0(4): 47-48.
The specimen which was used for predicting residual cycle life of turbine disk had been machined by electrical discharge machining technique.The size of precracking source is width 0.05mm±0.025mm,deep 0.25mm±0.013mm and length 1 mm±0.05mm.A fatigue crack of length 1.50 mm±0.13mm on the specimen was made by fatigue testing,and the residual cycle life of specimen with precracking source had been determined.
